Through this application, Baylor College of Medicine responds to RFA: DK-02-017, MTOPS Prostate Samples Analysis Consortium (MPSA). The Baylor Prostate Center proposes to serve as a Biomarker Unit within the MPSA consortium, which will work cooperatively with the other Biomarker Units, the Pathology Coordinating Center, and the NIDDK Project Coordinator to perform basic and translational research on biomarkers for BPH. The PI, Kevin M. Slaw/n, M.D., Director of the Baylor Prostate Center, recruited and managed 200 patients on the MTOPS trial over its seven-year duration. The co-investigators encompass broad interests and expertise in both clinical and basic research in benign prostatic hyperplasia (BPH), molecular epidemiology, biomarkers research, genetic and tissue microarray technology, cell signaling, and sophisticated data mining and statistical analysis of complex biologic data. Drawing from his extensive BPH clinical trials experience and with the resource management skills gained as co-Director of both the Biopsy and the Basic Tissue Research Committees of the MTOPS trial, as the Serum Bank director and member of the Resource Allocation Committee of the Baylor SPORE in Prostate Cancer, and as director of Baylor's Prostate Cancer Screening Program for the past eight years, the PI has the requisite administrative, clinical and basic research experience in BPH and biomarker development and validation to lead this center. Furthermore, the considerable tissue resources available through BPH-sub-studies of the Baylor SPORE in Prostate Cancer, and the expertise in tissue harvesting, cataloguing and banking, and in tissue microarray development and production will serve as a valuable resource for biomarker validation prior to testing on the invaluable and limited MTOPS tissue for the Baylor Center, as well as, for the other MPSA consortium members. Our large prostate cancer screening serum bank, containing frozen sera obtained through a yearly program, contains serial frozen serum samples and clinical data including IPSS, DRE estimated prostate volume, and medical and surgical treatment history for BPH on over 10,000 patients spanning a decade of follow-up. Serum markers that correlate with the presence and severity of BPH or that predict progression or response to medical therapy, identified either by the Baylor Biomarkers Center, or by other Centers could be validated in a Phase II study with these resources, allowing only the best markers for progression to evaluation in Phase III studies using the exhaustible MTOPS serum and tissue bank resources. Through the efforts of this RFA proposal, the Baylor MPSA Center, along with the other centers, the Biostatistics Center and the NIDDK, hopes to answer identify and validate much needed new biomarkers for the detection of BPH and the assessment of risk for disease progression, as well as to gain insight into the molecular correlates that determine response to medical therapies, primarily a-blockers and 5a-reductase inhibitors for this disease.